Magneto-interrupter.



W. E. DOW.

MAGNETO INTERRUPTER.

v APPLIUATION FILED JUNE 16, 1908. 975,842, Patented N0v.15, 1910;

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' W. B. DOW.

MAGNETO INTERRUPTER.

.urmonmn rum) mm 1a, 1908.

Patented Nov. 15, 1910.

2 SHEETS-SHEET 2.

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WILLARD E. DOW, F BRAINTREE, MASQACHUSETTS.

MAGNETO-INTERRUPTER.

Specification of Letters Patent.

Patented Nov. 15, 1910.

Application filed Tune 16, 1908. Serial No. 438,?58.

flb all whom it may concern:

Be it known that I WILLARD" E. Dow, a citizen of the United tates, and resident of Braintree, in the county of Norfolk and State of Massachusetts, have invented an Improvement in Magneto-Interrupters, of which the following description, in connection with the accompanying drawings, is a specification like letters on the drawings representing like parts.

My invention 'has for its object the provision of means for adjusting the interrupter while the engine is going, and leaving the terminals of the interrupter axially undisturbed with relation to each other.

My invention also includes means for giving extremely accurate, smooth adjusting movement, besides various minor improvements, all of which will be pointed out more at length in the course of the following description, reference being had to the accompanyingdrawin s, in which I have shown a preferred embo iment of the invention.

In the drawings, Figure 1 represents in side elevation a magneto provided with my invention, the constructional details of the latter being shown in vertical longitudinal section; Fig. 2 is an end elevation, looking at the right, Fig. 1; Fig. 3 is an end elevation of the interrupter and chamber with the cap and adjusting device removed; Fig. 4 is a view in elevation, looking at the inside, of the adjusting ring and cap; and

Fig. 5 shows the assembled parts in side elevation.

The magneto itself may be of any construction desired, comprising as herein shown fixed magnets'l, 2 mounted on a base 3 and containing an armature l rotating between usual pole pieces (not shown) secured to said magnets, etc. The interrupter is mounted, as usual, at the right hand end and preferably rotates with the armature, to which it is secured by an axial insulated rod 5. The movable member 6 of the interrupter is carried by a block 7 mounted on a spring 8 in the form of a double helix, see Fig: 3, i. c. it continues from the block 7 around the box or inclosing chamber in opposite directions, the two members 9 and 10 of said spring meeting at 11, whence an extension 12, preferably in the same plane as the parts 9 and 10, extends toward the center of the chamber and is secured by a bolt 13 preferably to the inner side of an angular arm 14 held fast by nuts 1.5 to the rod .3 to turn therewith. The arm 14 extends angularly at its free end, see Fig. 1, and carries the stationary terminal 16 of the interrupter to cooperate with the movable terminal 6. By having the spring 8 permanently secured to the arm 14 so that the entire mechanism carrying the interrupter becomes practically one part, it becomesvery easy to take out the interrupter for examination. All that is necessary 1s to remove the nuts and slide out the entire interrupter mechanism as one piece, instead of taking each portion thereof out. separately as heretofore.

The main object of my invention .is to provide means for adjusting theinterrupter while the engine is going. Having the spr ng extend around similarly at the opposite sides of the block 7 is one feature which facilitates this object, as thereby the operation of the interrupter or the separation of its terminals is much more steady. The main adjusting means, in the embodiment of my invention herein shown, consists of an externally operable rotary adjusting device, herein shown as a ring 17 having threaded engagement at 18 with a stationary boss 19, and having at its outer end a threaded flange 20 on which is mounted a clamping ring 21 whose flange 22 clamps in accurate position the cam ring 23 whose opposite pro ecting cam surfaces 24, 25, Fig. 4t, operate" the interrupter by their engagement with the tripping block 7 which actuates the movable terminal 6 of the in terrupter terminals. The means by which the ring 23 is. held accurately in position is also, in and of itself, an important feature of invention. 'Said means consists of a thin projecting steel plate or ring 26 held by screws 27 immovably clamped between the ring :23 and an annular wall or carrying member 28 which constitutes also the wall of the interrupter. chamber or box which contains the operative devices thus far explained. The member 28 is provided with a handle 29 whereby it may be rocked, and has a projecting finger or lug 30 to engage opposite screw stops 31, 32 adjustably mounted in arms 33 in the path of movement of said lug 30. The edge of the adjusting ring 17 is notched at 84 to tacilitate turning it, and also to engage a spring detent 35 for holding it in accurate ad ustment into whatever position it may be moved. Thus by turning the adjusting ring 17 on the threads 18 the cam ring 23 may be moved out or with the utmost delicacy, thereby correspondingly adjusting the interrupter by moving the movable terminal i 6 inwardly or outwardly as the case maybe,

and this adjustment can be made at any time, irrespective of whether the machine is running or not. Likewise by turning the handle 29, the point of interruption may be advanced or retarded while the machine is running. By having the thin, stifi plate or flange 26 held against the edge of the ring 17, the movement of the cam ring is controlled so that it' is absolutely accurate in one and the same plane perpendicular to the axis 5,"and by having said flange 26 not only thin and stiff but preferably made of steel, the adjusting movement thereof is smooth. It will be understood that the clamping ring 28 is brought into delicate clamping engagement with said flange 26 just sutlicient to hold it against lateral play and yet permit it to turn circumferentially, said clamping ring being fastened immovablyby thering 21 and a set screw 36, Fig. 5, when properly adjusted. The wall member 28 is threaded at 37 to receive a. cap 38 of insulating material, such as hard rubber, in which is centrally mounted a binding post 39 (Patent No. 821,029,May 22,19Q6) whose carbon terminal 40 bears against the end of the rod 5 for receiving a conductor wire to constitute the ground terminal of the magneto. By .providing'this insulator cap 38 for the ground terminal, I eliminate all the elaborate insulation of posts, etc., of the aforesaid patent, and moreover provide a very convenient removable cover construction. To prevent the inadvertent removal of the'adjusting ring 17 when removing the clamping ring for inspecting the interior of the mechanism, I provide a stop of any suitable form, herein shown as a screw 41 whose head overhangs the threaded edge of the ring 17, see Fig. 1. This stop also prevents when either terminal is rotated, but, by my invention, they are left always in the same with relation to each other, and the terminals are simply adjusted tocome toward each other longitudinally as they wear away. It -will readily be understood also that this adjustment is readily accom lished while the magneto is running, simp y by rotating the adjusting ring 17 outwardly. Likewise the timing of the magneto is similarly varied while the magneto is running simply by moving the timing lever'29, and further-. more by adjusting the stop screws 31, 32 the timing lever may be permitted to have a maximum throw or a minimum throw as desired.

lVithout elaborating upon the invention more at length, it will be sufficient to point out that I consider it as broadly new in many respects, as will be more apparent from the appended claims, and accordingly I wish it understood that I am not limited to the details of construction herein set forth as the preferred embodiment, inasmuch as many variations in form, arrangement and combination of parts may be resorted to without departing from the spirit and scope of my invention.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a magneto, a rotary part, a current interrupter, having its terminals rotated by said part, and means for adjusting said terminals toward and from each other while they are being rotated.

2. In a magneto, an interrupter having cooperating make-and -break terminals, means including a rotary'part for operating said terminals, an operating cam having the double function of determining the separating distance of said terminals and of regulating the timing of the interruptions, an externally operable ad usting ring threaded onto an adjacent part for moving said cam in one direction to regulate the separation of said terminals, and externally operable rotary means for moving said cam in another direction for regulating the timing.

3. In a magneto, an interrupter, comprising a fixed contact and a movable contact,

yielding means supporting the movable contact, a cam projection for operating said movable contact, said cam projection being movable with relation to said contacts in two directions, one for varying the timing and the other for varying the 'se arating distances of the contacts, means or relatively rotating said contacts and said cam projection-to operate the interrupter, external means for changing the operating position of said cam projection with relation to said contacts without relatively moving said contacts for varying the timing of the 1nagneto,.said external means being adjustable while the magneto is running, adjustable stops for said timing means, to permit or a maximum throw of the latter, or a minimum throw, as desired, and means for relatively moving said cam and said contacts to regulate the separating distance. of the contacts.

In a magneto, an interrupter, oomprising a fixed contact and a cooperating movable Contact, spring means yieldingly sup porting said movable contact, having two oppositely extending curved portions fixedly supported at their ends opposite the contacts, whereby the movable Contact is rendered capable of moving longitudinally toward and from the nuint with said fixed contact, and cooperating adjusting means for adjusting the nornial position of said movable contact toward or from said fixed contact.

l'n-a magneto, an interrupter, having a fixed Contact, a movable contact, a yielding supporting means for the latter, a trippingcam ring foroperating said movable contact, means for relatively rotating said contacts and said ring, guiding means for guiding said ring in an unvarying path of adjustment, said guiding means including a stifl, thin'fiange riding in an annular groove, and timing means adjusting said ring to change the timing of the magneto.

6, In a magneto, a central rotary member, an interrupter and fixed and movable confixed Contact, and is. held at all times in unchanging axial illlle;

tacts carried thereby, a tripping-cam ring, an annular timing member provided with a thin, stiff, peripheral flange, secured to the ring and means providing an annular groove for said flange to travel in for guiding said-ring in an unvarying path with relation to the path of rotation of said interrupter. v or v p L ina'iiiagneto. a central rotary member,

"an interrupter and fixed and movable contacts carried thereby, a tripping-cam ring, an annular timing member provided With a thin, stiff, peripheral flange, secured to the ring and I means including an adjustable clamping ring and coiiperating member providing between them an annular groove for said peripheral flange to travel in forguiding said ring ii'fan unvarying path With relation to the path of rotation of said inter- 'rupt'er. r In testimony whereof, I have signed my name to this specification, two subscribing witnesses.

WILLARD E. DOXV.

in the presence of Witnesses:

M. J. SPALDING, EDWARD MAXWELL. 

